Pressure regulating valves for a variety of applications have been known for many years. One application is that of controlling the temperature of a fluid in a fluid circulation system by controlling fluid pressure in the system. Most frequently, this is accomplished by means of complicated valves having a number of sliding parts.
In one application, a pressure regulating valve is required in a two phase thermal management system designed for use in space stations. It is important in such applications to have an integrated thermal management system to control component temperature and one technique for providing constant temperature with variable heat loads is to use a two phase thermal management system where liquid is circulated through the components and partially vaporized by heat extracted from the components. In such application, the mixture of liquid and vapor leaving the components is transported to a condenser where heat is rejected to space by means of a radiator.
In practice, the failure of valves in space-related systems has been a serious problem. Conventional valves having moving and/or sliding parts such as that disclosed in Bayles U.S. Pat. No. 1,546,466 fail to meet the stringent reliability requirements for space qualified thermal cooling systems since they can easily stick due to the close tolerances of the relatively movable parts and the fact that they do not have sufficient force to overcome any impediment to normal movement. Moreover, it is well known that conventional valves can wear over time leading to failure.
Among other attempts to provide valves for various applications are those disclosed in U.S. Pat. Nos. 3,097,664; 3,583,432; and 3,805,823.
While overcoming problems of the type indicated hereinabove, it is desirable to provide a reliable pressure regulating valve to control fluid pressure to a fixed delta pressure above a sensed vapor pressure. It is also desirable to provide a pressure regulating valve which is self-powered and has no sliding parts. Further, it is desirable to provide a pressure regulating valve for use in space stations where individual pieces of equipment and experiments can be plugged into a thermal bus as needed.
The present invention is directed to overcoming the above stated problems and accomplishing the stated objects.